WHO types A and AB thymomas

Not always benign

Rohit K. Jain, Rutika J. Mehta, John D. Henley, Kenneth Kesler, Patrick Loehrer, Sunil Badve

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

The 2004 WHO classification of thymic tumors recognizes five major subtypes of thymomas and thymic carcinoma. Subtypes A and AB thymomas are purported to be benign neoplasms, although prior studies have suggested a potential for malignant behavior. The purpose of this study was to assess the clinical behavior of A and AB thymomas identified from a large institutional pathologic database. A retrospective slide review of 500 thymic epithelial tumors identified 71 (14%) cases of types A and AB thymomas. Clinical history and follow-up information were obtained through retrospective chart review. There were 38 and 33 cases of types A and AB thymomas, respectively. Complete follow-up data were available in 37 (52%) cases. Eighteen (49%) patients (type A, n9 and type AB, n9) had evidence of recurrent/metastatic disease at an average of 62 months (range from 6 to 244 months) after initial diagnosis. Survival curves for patients with types A and AB thymomas, with and without recurrences, show a statistically significant difference (P=0.001 and 0.005, respectively). Analysis of this large cohort confirms the potential for subtypes A and AB thymomas to show malignant behavior. Long-term clinical monitoring, therefore, appears to be justified in these cases. This study also shows the poor correlation between the WHO classification and tumor behavior.

Original languageEnglish
Pages (from-to)1641-1649
Number of pages9
JournalModern Pathology
Volume23
Issue number12
DOIs
StatePublished - Dec 2010

Fingerprint

Thymoma
Thymus Neoplasms
Neoplasms
Cohort Studies
Databases
Recurrence
Survival

Keywords

  • thymoma
  • type A
  • type AB
  • WHO

ASJC Scopus subject areas

  • Pathology and Forensic Medicine

Cite this

WHO types A and AB thymomas : Not always benign. / Jain, Rohit K.; Mehta, Rutika J.; Henley, John D.; Kesler, Kenneth; Loehrer, Patrick; Badve, Sunil.

In: Modern Pathology, Vol. 23, No. 12, 12.2010, p. 1641-1649.

Research output: Contribution to journalArticle

Jain, Rohit K. ; Mehta, Rutika J. ; Henley, John D. ; Kesler, Kenneth ; Loehrer, Patrick ; Badve, Sunil. / WHO types A and AB thymomas : Not always benign. In: Modern Pathology. 2010 ; Vol. 23, No. 12. pp. 1641-1649.
@article{18a08a44072347a5ae44dde14c6119cb,
title = "WHO types A and AB thymomas: Not always benign",
abstract = "The 2004 WHO classification of thymic tumors recognizes five major subtypes of thymomas and thymic carcinoma. Subtypes A and AB thymomas are purported to be benign neoplasms, although prior studies have suggested a potential for malignant behavior. The purpose of this study was to assess the clinical behavior of A and AB thymomas identified from a large institutional pathologic database. A retrospective slide review of 500 thymic epithelial tumors identified 71 (14{\%}) cases of types A and AB thymomas. Clinical history and follow-up information were obtained through retrospective chart review. There were 38 and 33 cases of types A and AB thymomas, respectively. Complete follow-up data were available in 37 (52{\%}) cases. Eighteen (49{\%}) patients (type A, n9 and type AB, n9) had evidence of recurrent/metastatic disease at an average of 62 months (range from 6 to 244 months) after initial diagnosis. Survival curves for patients with types A and AB thymomas, with and without recurrences, show a statistically significant difference (P=0.001 and 0.005, respectively). Analysis of this large cohort confirms the potential for subtypes A and AB thymomas to show malignant behavior. Long-term clinical monitoring, therefore, appears to be justified in these cases. This study also shows the poor correlation between the WHO classification and tumor behavior.",
keywords = "thymoma, type A, type AB, WHO",
author = "Jain, {Rohit K.} and Mehta, {Rutika J.} and Henley, {John D.} and Kenneth Kesler and Patrick Loehrer and Sunil Badve",
year = "2010",
month = "12",
doi = "10.1038/modpathol.2010.172",
language = "English",
volume = "23",
pages = "1641--1649",
journal = "Modern Pathology",
issn = "0893-3952",
publisher = "Nature Publishing Group",
number = "12",

}

TY - JOUR

T1 - WHO types A and AB thymomas

T2 - Not always benign

AU - Jain, Rohit K.

AU - Mehta, Rutika J.

AU - Henley, John D.

AU - Kesler, Kenneth

AU - Loehrer, Patrick

AU - Badve, Sunil

PY - 2010/12

Y1 - 2010/12

N2 - The 2004 WHO classification of thymic tumors recognizes five major subtypes of thymomas and thymic carcinoma. Subtypes A and AB thymomas are purported to be benign neoplasms, although prior studies have suggested a potential for malignant behavior. The purpose of this study was to assess the clinical behavior of A and AB thymomas identified from a large institutional pathologic database. A retrospective slide review of 500 thymic epithelial tumors identified 71 (14%) cases of types A and AB thymomas. Clinical history and follow-up information were obtained through retrospective chart review. There were 38 and 33 cases of types A and AB thymomas, respectively. Complete follow-up data were available in 37 (52%) cases. Eighteen (49%) patients (type A, n9 and type AB, n9) had evidence of recurrent/metastatic disease at an average of 62 months (range from 6 to 244 months) after initial diagnosis. Survival curves for patients with types A and AB thymomas, with and without recurrences, show a statistically significant difference (P=0.001 and 0.005, respectively). Analysis of this large cohort confirms the potential for subtypes A and AB thymomas to show malignant behavior. Long-term clinical monitoring, therefore, appears to be justified in these cases. This study also shows the poor correlation between the WHO classification and tumor behavior.

AB - The 2004 WHO classification of thymic tumors recognizes five major subtypes of thymomas and thymic carcinoma. Subtypes A and AB thymomas are purported to be benign neoplasms, although prior studies have suggested a potential for malignant behavior. The purpose of this study was to assess the clinical behavior of A and AB thymomas identified from a large institutional pathologic database. A retrospective slide review of 500 thymic epithelial tumors identified 71 (14%) cases of types A and AB thymomas. Clinical history and follow-up information were obtained through retrospective chart review. There were 38 and 33 cases of types A and AB thymomas, respectively. Complete follow-up data were available in 37 (52%) cases. Eighteen (49%) patients (type A, n9 and type AB, n9) had evidence of recurrent/metastatic disease at an average of 62 months (range from 6 to 244 months) after initial diagnosis. Survival curves for patients with types A and AB thymomas, with and without recurrences, show a statistically significant difference (P=0.001 and 0.005, respectively). Analysis of this large cohort confirms the potential for subtypes A and AB thymomas to show malignant behavior. Long-term clinical monitoring, therefore, appears to be justified in these cases. This study also shows the poor correlation between the WHO classification and tumor behavior.

KW - thymoma

KW - type A

KW - type AB

KW - WHO

UR - http://www.scopus.com/inward/record.url?scp=78649715497&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78649715497&partnerID=8YFLogxK

U2 - 10.1038/modpathol.2010.172

DO - 10.1038/modpathol.2010.172

M3 - Article

VL - 23

SP - 1641

EP - 1649

JO - Modern Pathology

JF - Modern Pathology

SN - 0893-3952

IS - 12

ER -